Descriptions

Construction of a wave energy facility is planned for a site off of Reedsport, Oregon. The initial licensed development will consist of ten buoys within a 0.25 mile2 area at depths of 50 - 69 m and will produce up to 1.5 megawatts (MW; Figure 1)a. A proposed project expansion (not currently licensed) could include 100 buoys that may occupy an area of approximately 1 mile x 5 miles and produce 50 MW (Figure 1)b.
Green sturgeon, currently listed as threatened under the U.S. Endangered Species Act (ESA), commonly migrate in oceanic waters along the U.S. West Coast at depths of 40 – 70 m during winter and spring months, which places the wave energy project directly within this species’ migratory corridor (Figure 1). Furthermore, given the proximity to the Umpqua River estuary (designated critical habitat), it is possible that the site selected for this wave energy project may be a concentration area for certain green sturgeon activities, such as feeding. An acoustic telemetry study has recently been funded to determine whether, and how, the proposed wave energy development may affect green sturgeon behavior and migration patterns. Outcomes of the study will include a determination of the potential cumulative impacts of the numerous ocean-energy projects planned for development along the U.S. West Coast. The study will have a Before-After design, with the Phase I “Before” [wave energy buoys] component planned for early 2013 to late Spring 2014, encompassing three oceanic migration periods. Phase I will gather baseline information on sex- and age-specific spatial and temporal patterns of habitat use. To these ends, we will deploy three parallel lines of acoustic telemetry receivers, oriented onshore/offshore, with the central line bisecting the wave energy development (Figure 1). The receivers, spaced closely enough in each line to yield a detection rate near 100%, will measure metrics including depth of detection, speed, and minimum transit distance through the array. Phase II, the “After” component of the study, will mirror the design of the “Before” component. Phase II results will be compared with Phase I results in order to determine if the fully operational wave energy installation affects patterns of habitat use. Phase II is unfunded at this time, but funding will be sought once the wave energy installation is more definite and is close to fully operational.
In addition to their relevance for green sturgeon along the U.S. West Coast, results of this study may also be used to evaluate the potential impacts of planned ocean energy projects on threatened or endangered sturgeons in the Atlantic ocean (e.g., Atlantic sturgeon) and in the Gulf of Mexico (e.g., Gulf sturgeon). Furthermore, this study will be useful for identifying potential impacts of this wave energy park to other acoustically-tagged species (e.g., white shark, which is currently under consideration for ESA listing).
Funding for this study will be provided by the Oregon Wave Energy Trust (OWET), NOAA, Southwest Fisheries Science Center, and the Northwest National Marine Renewable Energy Center (NNMREC).